Synchronizing mechanism for the seconds-hands of clocks



(No Model.)

H. MUNSON. SYNGHRONIZING MECHANISM FOR THE SECONDS HANDS OF CLOCKS.

Patented Sept. 1,1891.

object to improve the UNITED STATES PATENT OFFICE.

HOMER MuNsoN, on MENDOTA, ILLINOIS.

SYNCHRONIZING MECHANISM FOR THE SECONDS-HANDS 0F CLOCKS.

SIECIFICATION forming part of Letters Patent No. 458,716, datedSeptember 1, 1891. Application filed March 3,1891- $erial No. 383,597.(No model.)

To all whom it may concern:

Be it known that I, HOMER MUNsoN, a citizen of the United States,residing at Mendota, in the county of La Salle and State of Illinois,have invented a new and useful Imrovement in Synchronizing Mechanism forClocks, of which the following; is a specification.

My invention relates to mechanism for synchronizing clocks, and has forits principal structure and mode of operation of the mechanism. relatingparticularly to the correction of the seconds-hand.

The common synchronizing mechanism for clocks heretofore employed may bedescribed, generally, as follows: An electric circuit controlled at acentral point (as the observatory) and including all the clocks to besynchronized energizes clectro-magnets in each clock system, whichattract armatures mounted upon a pivoted lever arranged in properlocation to engage projecting pins upon the minute-hand-carrying disk.These pins are so located upon the disk (projecting laterally therefrom)that the predetermined period of synchronization shall be centralbetween two pins, and the latter shall normally extend in a horizontalplane with each other. The le ver, under the action of the armaturepressing downward upon any pin above this horizontal plane, causes thepin to take the shortest line to the horizontal plane, turning the diskforward or backward and advancing or returning the minutehand to thecentral point, which is usually at the noon or twelve-oclock point onthe dial of the hour. The gear connection of the hour-hand with theminutehand causes the former to be advanced or returned to the properextent. Generally the seconds-hand is also thus actuated by mechanism,whereby the synchronization may be effected in the fraction of a minute.So far as I am aware, however, the syehronization involving theemployment of an electric circuit has always been produced by a directaction between the armature-lever and the minute-hand disk orbetween thelever or a branch thereof and the seconds-hand, and especially in thecase of the last-described construction much uncertainty has resulted inthe operation of the mechanism. In a majority of cases wheresynchronizing is practiced the actual difference to be rectified is lessthan a minute, and especial accuracy in the action of the seconds-handis made necessary.

The purpose of my invention is to remedy defects in the synchronizingapparatus heretofore employed, one form of which is above described; andit consists, primarily, in actuating the seconds-hand in synchronizingby the clock-train released to perform its function by anelectro-magnetic apparatus; secondly, in a synchronizing mechanismwherein the seconds-han d is actuated by releasing. the escapement fromthe clock-train, thus permitting the latter to operate the seconds-hand;furthermore, in a synchronizing mechanism in which the secondshand issynchronized by the action of the clock-train released from theeseapement and provided with a catch to interrupt the revolution of theseconds-hand at a predetermined point, and, finally, in the preferredgeneral and specific construction which I employ, all as hereinaftermore fully described and claimed.

In the drawings, Figure l is a front elevation of the upper part of asynchronizing clock, showing my improvements; Fig. 2, a

vertical cross-section taken centrally through Fig. 1. Fig. 3 is adetail view showing the clutch-sections with interposed disk detachedfrom each other, and Fig. 4c a perspective view of the upper end of thecrank-arm which operates to open the clutch.

A represents the clock-train, (shown of the kind controlled by aspring,) andt t represent the escape-wheel and anchor, respectively,mounted as usual.

13 represents a lever, pivoted at s to extend across the front of theclock-frame in position to engage the pins upon the minute-hand disk inthe usual manner for clocks of this description. The lever B carries anarmature r at its outer end, which is attracted by the electro-magnets ron the closing of the circuit, the weight of the armature causing itsreturn when the circuit is broken. So far as relates to thesynchronizing of the minutehand the operation of the lever and disk isas heretofore-that is to say, the downward pressure of the inner part ofthe lever causes the alignment of two pins, thus bringing theminute-hand immediately opposite a fiveminute point on the dial. Themechanism for synchronizing the seconds-hand differs from that relatingto the correction of the minute hand in the essential particular that itis operated by the clock-train and not by a positive action by thelever, as by its downward pressure on the pins, and the means I preferto employ to bring about this improved mode of operation is as follows:

C represents the seconds-hand mounted on its arbor q. The scape-wheel iis carried by the seconds-hand arbor through the looselymounted sleeveq, and is caused to engage the arbor to revolve the same by a clutchmechanism D D as follows: The clutch-section D is formed upon theescapement-wheel t, and the clutch-section D is mounted on the sleeve 19upon the arbor q. The sections D and D are kept normally in engagementthrough their perimetal teeth by the coiled spring 0, surrounding thearbor q and bearing on one side against the flanged end 0 of the sleeve19 and on the other against the catch E on the arbor q. Between theclutch-sections D D is the disk E, which is mounted upon and revolveswith the arbor q, and a pin or pins 41 hold the disk F and theclutch-section D together in such manner that while they are caused torevolve together the section D may move toward and from the disk. Thisis accomplished by securing the pin 7% to the disk and causing it topass through a hole made in the section D.

E is a catch in the form of a finger carried by the seconds-hand arbor qand having at its outer end the square recess, as shown in Fig. 1. Itrevolves with the arbor in a vertical plane below the line of movementof the detent G, presently to be described.-

The lever B is provided on its rear face near its inner end with aprojection or cam m and near the latter with a perforated horizontalbearing-strip Z. The detent G, pivoted in the frame of the clock, hasthe rod Z extending downward therefrom, which rod is reduced at its1owcrend,where it passes through the perforation in the bearing Z. Thereduced part of the rod forms the shoulder Z through the medium of whichthe rod, and with it the detent, is raised. An inward-projecting bearingplate on the clock-frame carries the pivot-pin 70. Upon this pin ispivoted the crank-arm H, the upper end of which engages the flange 0' onthe sleeve 19, while the lower end carries the cam m, the location ofwhich, in the normal position of the parts, is immediately below theprojection in on the lever B. It will be understood that the detent Ghas a limit of movement at its free end, which keeps it normally abovethe line of movement of the catch E and at its lowermost position insuch line of movement, thereby to stop the revolution of the catch whenthe latter shall have reached a point in a vertical line above the arborq. Depending upon the desired point in the seconds-scale at whichsynchronization shall take place, the seconds-hand maybe coincident withor at an angle to the line of the catch E. Usually the synchronizing isdone at the minute, so that usually the seconds-hand and catch arecoincident. It follows that when the catch is detained by the detent ata point in a vertical line above the arbor the secondshand will point atsixty seconds.

The operation of the mechanism'is as follows: The clock being wound andin operation, an upward attraction of the free end of the lever Bdepresses its inner end, drawing down the detent G. In the movement ofthe lever the projection m engages the cam m at the end of the crank-armH, forcing it inward and causing the upper end of the crank-arm to pressoutward the sleeve 17 against the resistance of the spring 0, thusseparating the clutch-sections D D and releasing the section D, and withit the disk F, arbor q, seconds-hand O, catch E, and the clock-train,from the detaining action of the anchor t. The result is obvious. Theclock-train thus released immediately and with great speed revolves thearbor q, and thus the secondshand and catch, until the catch E reachesthe vertical position, where it is met by the detent G and detainedwhile the lever is in its attracted position. The release of the leverwhile causing the separation of the catch and detent at the same timecauses the release of the crank-arm H, permitting the spring 0 to reactto cause the re-engagement of the clutchsections, thus again placing theclock-train and other mechanisms under the control of the escapement.

What I claim as new, and desire to secure by Letters Patent, is-- 1. Ina cloclcsynclii'onizer, the combination, with the seconds-hand and theclocktrain, of a releasing device and a stop whereby the clock-train maybe released from the escapement and stopped at a predetermined point,substantially as described.

2. In a clock-synchronizer, the combination, with the seconds-hand,clock-train, and escapement, of a release between the escapement andclock-train and a stop located to prevent the operation of theclock-train when released at a predetermined point, substantially asdescribed.

3. In a clock-synchronizer,the secondshand, clock-train, and escapement,in combination with a clutch between the clock-train and scape-wheel, arelease for said clutch, a catch connected with the clock-train, and adetent adapted to engage said catch at a predetermined point,substantially as described.

i. A synchronizer for the seconds-hand of clocks, comprising, incombination, the sec onds-hand arbor geared with the clock-train, atwo-partclutchandescapementcontrollingthe clock-train, a catch movingwith the secondshand arbor, arranged to stop its movement at apredetermined point, and an. electrically actuated release for theclutch, arranged to operate substantially as described.

In aclock-synchronizer, the combination.

of the arbor q, clutch D D, mounted on separate sleeves upon the arbor,the disk between and engaging one of the clutch-sections and secured tothe arbor, the lever B, a connection between the lever and clutch torelease the same, and a detent and catch actuated through the lever B,substantially as described.

6. In a clock-syncl1ronizer,the seconds-hand arbor and catch thereon,the detent normally out of engagement with the catch and arranged toengage the same at a predetermined point, the lever actuating thedetent, the clock-train geared to operate the seconds-hand arbor, and aclutch and release connected with and operated by the lever to controland release the clock -train, substantially as described.

7. In a clock-synchronizer, in combination,

the arbor q, clutch D D, disk G, crank-arm H, engaging one of theclutch-sections, lever B, operating the crank-arm, and the catch anddetent operated by the lever B, substantially as described.

8. In a clook-synchronizer, the arbor q, carrying theseconds-hand, thecatch and the disk secured thereto, the clutch connected to and operatedin one movement by the disk, the escapement connected to and operatingthe disk in the other movement, a crank-arm e'ngaging and operating theclutch to open and close the same, a detent engaging the catch, and alever operating both the detent and the crank-arm in a single movement,substantially as described.

HOMER HUNSON.

In presence of= J. W. DYRENFORTH, M. J. FRosT.

